The earth is a very special planet - we don't realize how lucky we are

There are countless trillions of planets in the universe. Simple life is no doubt abundant on many planets, as it has been on earth for 3.5 billion years. However, complex life, which on earth took another 3 billion years to evolve from simple life, is likely uncommon. Because there are so many conditions necessary for it to exist, intelligent life, which took 3.5 billion years to evolve on earth, is probably very rare.

Many stars are unstable flare stars. Others are more massive than the sun and don't "live" long enough: some expand into red giants and the biggest explode into supernovae in a few million years. Many stars are part of multiple star systems and any planets would have unstable orbits and extreme fluctuations in their surface temperatures.

After over 50 years, SETI still hasn't heard any aliens communicating with each other out there. I'm sure intelligent life DOES exist on other planets throughout the universe, but it's not as common as some people believe.

I'm not denying there have been many UFO sightings, but those objects are all from earth: weather balloons, military planes, sun's glare on commercial aircraft, etc. UFOs from other worlds have not been visiting earth.

Mind you, virtually all the scientists agree there's probably lots of simple life on the trillions of planets out there. It only takes about 1,000,000,000 years, maybe less, for simple life to form on a fairly stable planet.

Sometimes we hear misleading news reports about "earth-like" planets being discovered. Yet there is no real evidence that those planets are anything like earth. I remember one report about a "newly-formed earth-like" planet being discovered around Fomalhaut, a massive class "A" star. Since the star's age is already estimated to be 500,000,000 years, Fomalhaut will expand into a red giant long before life could evolve on that planet.

Most of us don't know how lucky we are to have even come into existance. Our earth is very SPECIAL place in the universe.